What Does ISTG Mean?

This slang abbreviation helps get your point across to someone else

ISTG stands for:

I Swear To God.

You've likely heard this expression spoken out loud in everyday language. It's a close relative to the extremely popular OMG (Oh My God) acronym that has dominated the social web for years.

ISTG is one of those online acronyms that's not only difficult to take a wild guess at, but also very rarely used. Understanding how to interpret it if you do come across it online or in a text, however, can bring new meaning to the message or conversation.

How ISTG Is Used

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ISTG is used in a variety of ways to express emotional sincerity. Some of the most common ways to use ISTG are:

  • To communicate certainty when faced with skepticism. When someone doesn't believe you about something you know to be true, using ISTG might convince them that you're telling the truth.
  • To promise to change an action or behavior. If you or others have reason to believe that you can't or won't change something about yourself, you can use ISTG as a way to promise that you're serious about changing.
  • To make a threat seem more intimidating. If you want someone to stop doing something you don't like, you might be able to do so just by using ISTG to threaten aggressive action.
  • As a general interjection. In conversations where something goes against what a person believes to be good or acceptable, ISTG might be used as an abrupt exclamation similar to JFC or WTF for the purpose of expressing emotion.

Examples of How ISTG Is Used

Example 1

Friend #1: "U sure the essay is due tmrw??? I thought we had til Friday!!!"

Friend #2: "Istg the deadline is tmrw!! Mr. Jones reminded us in class today!!!"

In the above example Friend #1 doesn't believe a fact stated by Friend #2, so Friend #2 uses ISTG to communicate their certainty and seriousness about the fact.

Example 2

Friend #1: "Woke up feeling like I got hit by a truck. ISTG I'm never drinking again..."

Friend #2: "Lol, you said that last time too"

This second example is a classic demonstration of how a person might take an oath as a personal vow to change their actions or behavior. Friend #1 uses ISTG as a promise to quit drinking.

When You Shouldn't Use ISTG

The acronym ISTG is typically not appropriate for use in professional conversations or conversations where you want to remain respectful toward the other person/people. There are other ways to make yourself sound sincere.

Likewise, you probably also shouldn't use ISTG when speaking to anyone who's very religious or spiritual—out of respect for their beliefs. They might get offended by an expression like this.

A more vulgar and disrespectful variation of ISTG is ISTMFG, which stands for I Swear To Mother F***ing God. This one is far more rare, and because it's so vulgar, you'll want to be extra careful with using it in text or online conversations.